Inrush current identification in power transformers using weight functions

Identification of inrush current from other existing faults is an important issue in protection of the power transformers. In order to analyze the inrush current and the single phase to ground fault current from the harmonic point of view, it is necessary that a proper method is presented for identifying these two currents. The proposed method is based on the weight functions of the calculated vectors by the positive sequence harmonic components of the inrush and the single phase to ground fault current. Regarding the variation range of the weight functions in this study, the usefulness of the proposed method is illustrated.